Useful overview of PCBWay's capabilities. I might consider switching from JLCPCB.

Design critique - I would put the mounting holes further from the board edge, for added strength. The screw heads are going to overhang a certain amount anyway.

I suspect more and more hobbyists are using 3.3V microcontrollers like the ESP32, Raspberry Pi Pico, and countless Adafruit offerings. Unless you know your project won't need much processing power, I don't see much reason to use a 5V "ATmega..." -based Arduino these days. Much easier to use a cheap £2 32-bit overkill processor than to deal with running out of RAM, etc. Also, most advanced sensors I've seen have 3.3V logic levels now.